Reactive black dyes containing acetoxyethyl sulfone moiety

ABSTRACT

This invention relates to a reactive black dye containing acetoxyethyl sulfone compound and more particularly, to the reactive black dye containing acetoxyethyl sulfone compound of formula (1), which is characterized by lessening the loss of dyes in filtering process owing to the low solubility by introducing the aminophenyl-beta-acetoxyethyl sulfone moiety, saving the cost for waste water treatment by using a small amount of salt in salting-out process and furthermore obtaining bright color with high dyeing yield and good substantivity wherein M is an alkali metal atom, and wherein the compound of formula (1) is chosen from

The application is a 371 of PCT/KR 99/00144 Mar. 26, 1999.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a reactive black dye containing acetoxyethylsulfone moiety and more particularly, to the reactive black dyecontaining acetoxyethyl sulfone moiety of the following formula 1, whichis characterized by lessening the loss of dyes in filtering processowing to the low solubility by introducing theaminophenyl-β-acetoxyethyl sulfone moiety, saving the cost for wastewater treatment by using a small amount of salt in salting-out processand furthermore obtaining bright color with high dyeing yield and goodsubstantivity:

wherein M is an alkaline metal atom.

2. Description of the Related Art

Conventionally, salting-out method has been adapted in order to isolatedyes from reaction mixture after synthesizing the reactive dyes.However, if aminophenyl-β-sulphatoethylsulfone is used as anintermediate in the course of manufacturing vinylsulfone-based reactivedyes, spray-dry method is adapted or large amount of salts is usedbecause high water-solubility of dyes hinder the salting out. Theisolation of dyes by spray-drying or by using large amount of salts maycause environmental pollution with waste water containing a good dealdyes and salts and eventually require much expenses on sewage treatment.

Especially, reactive black aminophenyl-β-sulphatoethylsulfone group hasproblems such as putting a reddish hue and lowering its substantivitybecause of high water-solubility.

Recently, in some developed countries such as European countries and U.S. A., there is restriction on salt concentration in dye waterwaste,thus continuous studies have been conducted in order to obtain low-saltdye and succeeded in marketing. In addition, the liquid dyes are usedmore favorably because they can be exactly measured and from which theautomatization of dyeing process and the promotion of worker's healthcan be achieved. Therefore, the highly concentrated dyes by removal ofsalts are required for the manufacture of the stable liquid dyes.

Therefore, in comparison with dyes synthesized withaminophenyl-β-sulphatoethylsulfone group, salting-out is generallyeasier in the dyes synthesized with aminophenyl-β-acetoxyethylsulfonegroup of following formula 2, which has relatively low water solubility:

In synthesizing process of dyes with usingaminophenyl-β-acetoxyethylsulfone group of the above formula 2, it ispossible to lower the concentration of salt in water waste because onlya small amount of salt is used in salting-out process than theconventional dyes. Also, it is cost-effective in sewage treatmentbecause only a small amount of dyes is lost during the filtering owingto low solubility of dyes. Furthermore, thus prepared dyes has a highpurity containing a small amount of salt and be able to lower theconcentration of salt and make it easier desalting process inmanufacturing liquid dyes.

The composition of the above formula 2 is already known and itsmanufacturing method is also disclosed in various documents. Among themethod, one preparation method of 4-aminophenyl-β-acetoxyethylsulfone isexpressed in the following Scheme1(Japanese unexamined publication Sho81-22354; German Patent No 2 929 107):

According to the above Scheme1, 4acetaminophenyl-β-hydroxyethylsulfoneand 98% of sulfuric acid is reacted to get a mixture of 70% of aboveformula 2 and 30% of above formula 3, and it is reported that the dyessynthesized with the mixture shows good dyeing properties. However, ithas a problem that the substantivity is lowered because of highwater-solubility due to the existence of4-aminophenyl-β-sulphatoethylsulfone.

But no report has been made on synthesizing reactive black dyesintroducing aminophenyl-β-acetoxyethylsulfone group of the above formula2.

SUMMARY OF THE INVENTION

As a result of continuous studies in order to prepare reactive blackdyes of high yield rate and high purity, the inventors completed thisinvention by synthesizing a reactive black dye introducingaminophenyl-β-ethoxyethylsulfone as a reactant.

Therefore, the object of this invention is to provide a reactive blackdye of high brilliance, low degree of water-solubility and fixation,having acetoxyethylsulfone group, which decrease the amount of pollutantin process for manufacturing dye.

DETAILED DESCRIPTION OF THE INVENTION

This invention is characterized by a reactive black dye which iscombined with compounds having acetoxyethylsulfone group of thefollowing formula 1:

wherein M is an alkaline metal atom.

This invention is described in more detail as follows:

The reactive black dyes having acetoxyethylsulfone group of the aboveformula 1 according to this invention may be prepared in varioussynthesizing methods according to the kind of starting material used.For example, the following Scheme2 shows the preparing method of areactive black dye with using aminophenyl-β-acetoxyethylsulfone as astarting material and the following Scheme3 shows another method withusing aminophenyl-β-hydroxyethylsulfone as a staring material.

According to the following Scheme2, the reactive black dye is preparedby (a) diazotizing aminophenyl-β-acetoxyethylsulfone compound; (b)neutralizing 1-naphtol-8-amino-3,6-disulfonic acid compound with acidgroup; and (c) mixing two reaction solutions prepared in the manners asdefined in (a) and (b) at temperature 0-5° C. and stirring the mixturewith adjusting the pH below 7 through adding acid.

wherein M is an alkaline metal atom.

Hereunder, the preparation method according to the above Scheme2 isdescribed more in detail.

Aminophenyl-β-acetoxyethylsulfone of formula 2 is diazotized. Thediazotization method adapted in this invention is conventional one,which means that after dispersing aminophenyl-β-acetoxyethylsulfone inwater at 0-5° C., the diazotzation reaction is carried with adding conc.hydrochloric acid and NaNO₂.

And through neutralizing 1-naphthol-8-amino-3,6-disulfonic acid withusing base in another reaction vessel, sulfonic acid group (—SO₃H) of1-naphthol-8-amino-3,6-disulfonic acid is transformed into sulfonic acidmetal salt (—SO₃M). The bases conventionally used in this reaction arealkaline metal hydroxide and alkaline metal carbonate salt andpreferably NaOH, LiOH, Na₂CO₃ and Li₂CO₃ are used. The amount of base isdetermined by equivalent rate to the amount of1-naphthol-8-amino-3,6-disulfonic acid.

After the reaction, the neutralized solution of1-naphthol-8-amino-3,6-disulfonic acid is cooled down below 5° C. withice, which is to carry out the coupling reaction with diazo compound at0-5° C.

After mixing the above diazo compound and the neutralized solution of1-naphthol-8-amino-3,6-disulfonic acid and adding base, the reactionsolution is stirred at below pH 7 at 0-5° C. and resulted in reactiveblack dye of above formula 1. The amount of diazo compound is preferable2-3 equivalent weight rate to 1-naphthol-8-amino-3,6-disulfonic acid. Ifthe amount get out of the scope, side reaction may be occurred. If thepH of reaction solution exceeds 7, there is a problem in that thereaction group is hydrolyzed. If the reaction temperature becomes below0° C., the reaction is not occurred satisfactorily and in the case ofexceeding 5° C., side reaction may be occurred.

Aminophenyl-β-acetoxyethylsulfone of the above formula 2, which is usedas a starting material in the above Scheme2 is prepared by reactingacetaminophenyl-β-hydroxyethylsulfone with acetic acid solutioncontaining hydrochloric acid.

With the preparation method according to the above Scheme2, whereinaminophenyl-β-acetoxyethylsulfone compound of the above formula 2 isused as a starting material, bright colored and high purity dyes can besynthesized which cannot be acquired withaminophenyl-β-sulfatoethylsulfone.

Particularly, aminophenyl-β-acetoxyethylsulfone of formula 2 has nosulfonic acid group (—SO₃H), which existed inaminophenyl-β-sulfatoethylsulfone of formula 3, so that the amount ofalkali used in neutralization for coupling reaction can be reduced.Furthermore, in comparison with the conventional method of followingformula 4, in which aminophenyl-β-sulfatoethylsulfone of formula 3 isused, the preparation method according to Scheme2 withaminophenyl-β-acetoxyethylsulfone of formula 2 as a starting materialhas little amount of by product and it is advantageous in obtainingbright colored dye just with spray-drying the reaction solution.

In isolation process of dye, salting-out is impossible due to the highdegree of water solubility of dye of formula 4 but this invention makeit possible to obtain pure dye of high degree of concentration, whichcontain small amount of salt and by product with salting-out isolationprocess of reactive black dye of formula 1 according to this invention.

Another method for preparing a reactive black dye of formula 1 accordingto the invention is defined in the following Scheme3.

According to the following Scheme3, the reactive black dye of formula 1is prepared by (a) diazotizing aminophenyl-β-hydroxyethylsulfonecompound; (b) neutralizing 1-naphtol-8-amino-3,6-disulfonic acidcompound with acid group; (c) mixing two reaction solutions prepared inthe manners as defined in (a) and (b) at 0-5° C. and stirring themixture with adjusting the pH below 7 through adding acid; and (d)dissolving the intermediate of formula 6 prepared in the manners of (a),(b) and (c) with anhydrous acetic acid and stirring the solution at80-90° C.

But the preparation method of Scheme3 has a problem that small amount ofred by-product are made during the reaction and the intermediate offormula 6 should be reacted with anhydrous acetic acid after completelydried.

The reactive dye according to the invention is distinguished by highdegree of fastness in case of dyeing to fabrics such as cotton, wool andsilk. Further, the reactive black dye of formula 1 shows better coloryield, fixation and fastness than the dye of formula 4.

The following specific examples are intended to be illustrative of theinvention and should not be construed as limiting the scope of theinvention as defined by appended claims.

Manufacturing Example: Preparation of4-aminophenyl-β-acetoxyethylsulfone

After attaching condenser with rubber balloon to reaction vessel of 100ml, 60 g (1 mol) of acetic acid and 1.8 g (0.1 mol) of water are putinto it. With maintaining the reaction solution at 15° C., 5.5 g (0.15mol) of hydrogen chloride gas is added slowly for 1.5 to 2 hours. Afteradding 24.3 g (0.1 mol) of 4-acetaminophenyl-β-hydroxyethylsulfone, thesolution, whose temperature is slowly raised to 70˜75° C. is stirred for9 hours.

Then the solution is cooled down to room temperature with slow stirring,filtered and rinsed twice with acetic acid (5 ml). After drying thefiltered solid at 60° C. in vacuum and dispersing it at 10 g of ice and25 ml of water, this solution is neutralized with 10% of sodiumcarbonate solution and filtered the crystals. With rinsing with water (5ml) three times and drying, white pure 20.6 g of4-aminophenyl-β-acetoxyethylsulfone (yield 84.8%, purity 97.5%) in solidtype is obtained. melting point: 92-93° C.

EXAMPLE 1

3N NaNO₂ (40 ml, 0.12 mol) is added to the dispersed solution of 26.76 g(0.11 mol) 4-aminophenyl-β-acetoxyethylsulfone and 200 ml of water, withmaintaining the temperature at 0-5° C. and 90 g of ice is added; this isfollowed by the addition of 24 ml (0.276 mol) of 35% HCl and anddiazotization. The diazotization is completed and excess nitrous acid isthen destroyed by means of sulfamic acid.

15.97 g (0.05 mol) of 1-naphthol-8-amino-3,6-disulfonic acid isdissolved in 200 ml of water, neutralized with 2.0 g (0.05 mol) of NaOHand is cooled down to 0-5° C. The diazotized solution is added at onceto 1-naphthol-8-amino-3,6-disulfonic acid neutralization solution andthen it is reacted with maintaining pH below 7 by means of slow additionof NaOH solution. In the middle of reaction, 30 g of ice is added threetimes in order to prevent the raise of temperature. The reaction isended after 4 hours of stirring and then reactive dyes is obtained byspray-drying.

¹H-NMR(300 MHz, DMSO-d₆): δ1.75(3H, s), 1.77(3H, s), 3.73(2H, t),3.79(2H, t), 4.28(4H, q), 7.42(1H, s), 7.48(1H, s), 7.92(2H, d),8.00(2H, d), 8.03(2H, d), 8.26(2H, d), 10.41(1H, s), 10.61(1H, s),15.36(1H, s)

EXAMPLE 2

An intermediate is prepared by coupling reaction in the same manner ofExample 1 except using 4.06 g of 4-aminophenyl-β-hydroxyethylsulfoneinstead of 4-aminophenyl-β-acetoxyethylsulfone. After adding 20 mlanhydrous acetic acid to 1 g of dried intermediate, it is reacted for 8hours at 80-90° C. and resulted in reactive black dyes.

EXAMPLE 3

3-aminophenyl-β-acetoxyethylsulfone is dispersed with 120 ml of waterand 19.0 ml (0.22 mol) of 35% HCl is added. The temperature ismaintained at 0˜5° C. and then 60 g of ice is added. The solution isdiazotized by means of addition of 3N NaNO2 (40 ml, 0.12 mol). Thediazotization is completed and excess nitrous acid is then destroyed bymeans of sulfamic acid.

15.97 g (0.05 mol) of 1-naphtol-8-amino-3,6-disulfonic acid is dissolvedin 120 ml of water, neutralized with 2.0 g (0.05 mol) of NaOH and cooleddown to 0-5° C. The diazotized solution is added at once to1-naphthol-8-amino-3,6 -disulfonic acid neutralization solution and thenit is reacted with maintaining pH below 7 by means of slow addition ofNaOH solution. In the middle of reaction, 25 g of ice is added threetimes in order to prevent the raise of temperature. The reaction isended after 4 hours of stirring and then reactive black dye is obtainedby salting-out and filtering.

¹H-NMR(300 MHz, DMSO-d₆): δ1.75(3H, s), 1.76(3H, s), 3.78(2H, t),3.82(2H, t), 4.30(2H, t), 4.32(2H, t), 7.41(1H, s), 7.48(1H, s),7.66-7.81(3H, m), 7.92(1H, d), 8.27(1H, d), 8.29(1H, s), 8.37(1H, d),8.61(1H, s), 10.37(1H, s), 10.49(1H, s), 15.47(1H, s)

Experimental Example

The reactive black dye prepared by the above Example 1 is used forexhaust-dyeing the fabrics such as cotton, wool and silk. After dyeingthe fabrics in line with Remazol Black B (formerly Reactive Black 5) andabsorbency, it is compared with those dyed with Remazol Black B.

Dyeing Method of Cotton Fabric

0.02 g (1.0% o.w.f dyeing) and 0.04 g(2.0% o.w.f. dyeing) of eachreactive black dye obtained from the above Example 1-2 and 0.06 g(3.0%o.w.f. dyeing) of Remazol Black B are dissolved in 25 ml of water; tothis solution 2 g of cotton fabric is introduced at 30° C. and 0.75 g ofsodium sulfate is added. The temperature is raised then to 50° C. and0.5 g of sodium carbonate is added. Dyeing is carried for 60 minutes andrinsed with cold water. The fabric is soaped off at 98° C. for 20minutes, is rinsed once more and is dried.

Dyeing Method of Wool Fabric

To 0.01 g (1.0% o.w.f. dyeing) of reactive black dye obtained from theabove Example 1 and Remazol Black B, 3 ml of buffer solution of pH 5 andwater is added to make 30 ml of salt solutions 1 g of wool fabric isintroduced to this solution and dyed for 60 minutes at 95° C. The fabricis then rinsed with cold water, is soaped off at 98° C. for 20 minutes,is rinsed once more and is dried.

Dyeing Method of Silk Fabric

To 0.01 g(1.0% o.w.f. dyeing) of reactive black dye obtained from theabove Example 1 and Remazol Black B, 3 ml of buffer solution of pH 7,0.6 g of sodium sulfate and water are added to make 20 ml of saltsolution. 1 g of silk fabric is introduced to this solution and dyed for60 minutes at 85° C. The fabric is then rinsed with cold water, issoaped off at 90° C. for 20 minutes, is rinsed once more and is dried.

When applied to cotton fabric, the reactive black dye of formula 1according to the invention shows excellent dyeing levelness andreproducibility. And in comparison with Remazol Black B of formula 4, itshows almost same degree of color yield, fixation and superior lightfastness (Dye of this invention: 4.5, Remazol Black B: 4). In otherfastness, it shows similar properties. Dye of formula 1 synthesizedaccording to Example 2 dyes fabric in red shade due to the redby-product produced during its synthesizing and its fixation value is 3%low than that of the dye prepared by the above Example 1 and its lightfastness of 3.5 is also low.

When applied to wool fabric, the reactive black dyes according to theinvention shows excellent dyeing levelness and reproducibility. And incomparison with Remazol Black B of formula 4, it shows superior coloryield (Dye of this invention: 16.43, Remazol Black B : 13.51), fixationand light fastness (Dye of this invention: 4, Remazol Black B : 3). Inother fastness, it shows similar properties.

When applied to silk fabric, reactive black dyes according to theinvention shows excellent dyeing levelness and reproducibility. And incomparison with Remazol Black B of formula 4, it shows almost samedegree of color yield and fixation and superior light fastness (Dye ofthis invention: 4, Remazol Black B: 3). In other fastness, it showssimilar properties.

As described in the above, the reactive black dyes of this invention useaminophenyl-β-acetoxyethyl sulfone as reaction group instead ofconventionally used aminophenyl-β-sulfatoethylsulfone, which can lessenthe wastes in manufacturing. In particular, it shows bright color andsuperior light fastness to Remazol Black B.

What is claimed is:
 1. A method for preparing a reactive black dye offormula 1, which comprises the steps of: (a) diazotizing anaminophenyl-β-acetoxyethylsulfone compound of formula 2; (b)neutralizing a 1-naphtol-8-amino-3,6-disulfonic acid compound with acid;and (c) mixing two reaction solutions prepared in the manners as definedin steps (a) and (b) at a temperature ranging from 0 to 5° C. andstirring the mixture with adjusting the pH below 7 through adding acid;wherein said aminophenyl-β-acetoxyethylsulfone compound of formula 2 ischosen from

wherein said reactive black dye of formula 1 chosen from

wherein M is an alkali metal atom.
 2. A method for preparing a reactiveblack dye of formula 1, which comprises the steps of: (a) diazotizing anaminophenyl-β-hydroxyethylsulfone compound of formula 5; (b)neutralizing a 1-naphtol-8-amino-3,6-disulfonic acid compound with acid;(c) mixing two reaction solutions prepared in the manners as defined insteps (a) and (b) at a temperature ranging from 0 to 5° C., stirring themixture with adjusting the pH below 7 through adding acid and preparingan intermediate of formula 6; and (d) dissolving said intermediate offormula 6 with anhydrous acetic acid and stirring the solution at atemperature ranging from 80 to 90° C.; wherein saidaminophenyl-β-hydroxyethylsulfone compound of formula 5 is chosen fromthe meta- and para-isomers of

wherein said intermediate of formula 6 is chosen from

wherein said reactive black dye of formula 1 is chosen from

wherein M is an alkali metal atom.